postgresql/contrib/pageinspect/sql/page.sql
Michael Paquier ddbd5d8731 Add to pageinspect function to make t_infomask/t_infomask2 human-readable
Flags of t_infomask and t_infomask2 for each tuple are already included
in the information returned by heap_page_items as integers, and we
lacked a way to make that information human-readable.

Per discussion, the function includes an option which controls if
combined flags should be decomposed or not.  The default is false, to
not decompose combined flags.

The module is bumped to version 1.8.

Author: Craig Ringer, Sawada Masahiko
Reviewed-by: Peter Geoghegan, Robert Haas, Álvaro Herrera, Moon Insung,
Amit Kapila, Michael Paquier, Tomas Vondra
Discussion: https://postgr.es/m/CAMsr+YEY7jeaXOb+oX+RhDyOFuTMdmHjGsBxL=igCm03J0go9Q@mail.gmail.com
2019-09-12 15:06:00 +09:00

97 lines
4.0 KiB
SQL

CREATE EXTENSION pageinspect;
CREATE TABLE test1 (a int, b int);
INSERT INTO test1 VALUES (16777217, 131584);
VACUUM test1; -- set up FSM
-- The page contents can vary, so just test that it can be read
-- successfully, but don't keep the output.
SELECT octet_length(get_raw_page('test1', 'main', 0)) AS main_0;
SELECT octet_length(get_raw_page('test1', 'main', 1)) AS main_1;
SELECT octet_length(get_raw_page('test1', 'fsm', 0)) AS fsm_0;
SELECT octet_length(get_raw_page('test1', 'fsm', 1)) AS fsm_1;
SELECT octet_length(get_raw_page('test1', 'vm', 0)) AS vm_0;
SELECT octet_length(get_raw_page('test1', 'vm', 1)) AS vm_1;
SELECT octet_length(get_raw_page('xxx', 'main', 0));
SELECT octet_length(get_raw_page('test1', 'xxx', 0));
SELECT get_raw_page('test1', 0) = get_raw_page('test1', 'main', 0);
SELECT pagesize, version FROM page_header(get_raw_page('test1', 0));
SELECT page_checksum(get_raw_page('test1', 0), 0) IS NOT NULL AS silly_checksum_test;
SELECT tuple_data_split('test1'::regclass, t_data, t_infomask, t_infomask2, t_bits)
FROM heap_page_items(get_raw_page('test1', 0));
SELECT * FROM fsm_page_contents(get_raw_page('test1', 'fsm', 0));
-- If we freeze the only tuple on test1, the infomask should
-- always be the same in all test runs. we show raw flags by
-- default: HEAP_XMIN_COMMITTED and HEAP_XMIN_INVALID.
VACUUM FREEZE test1;
SELECT t_infomask, t_infomask2, flags
FROM heap_page_items(get_raw_page('test1', 0)),
LATERAL heap_tuple_infomask_flags(t_infomask, t_infomask2) m(flags);
-- output the decoded flag HEAP_XMIN_FROZEN instead
SELECT t_infomask, t_infomask2, flags
FROM heap_page_items(get_raw_page('test1', 0)),
LATERAL heap_tuple_infomask_flags(t_infomask, t_infomask2, true) m(flags);
-- tests for decoding of combined flags
-- HEAP_XMAX_SHR_LOCK = (HEAP_XMAX_EXCL_LOCK | HEAP_XMAX_KEYSHR_LOCK)
SELECT heap_tuple_infomask_flags(x'0050'::int, 0, true);
SELECT heap_tuple_infomask_flags(x'0050'::int, 0, false);
-- HEAP_XMIN_FROZEN = (HEAP_XMIN_COMMITTED | HEAP_XMIN_INVALID)
SELECT heap_tuple_infomask_flags(x'0300'::int, 0, true);
SELECT heap_tuple_infomask_flags(x'0300'::int, 0, false);
-- HEAP_MOVED = (HEAP_MOVED_IN | HEAP_MOVED_OFF)
SELECT heap_tuple_infomask_flags(x'C000'::int, 0, true);
SELECT heap_tuple_infomask_flags(x'C000'::int, 0, false);
-- HEAP_LOCKED_UPGRADED = (HEAP_XMAX_IS_MULTI | HEAP_XMAX_LOCK_ONLY)
SELECT heap_tuple_infomask_flags(x'1080'::int, 0, true);
SELECT heap_tuple_infomask_flags(x'1080'::int, 0, false);
-- test all flags of t_infomask and t_infomask2
SELECT unnest(heap_tuple_infomask_flags(x'FFFF'::int, x'FFFF'::int, false))
AS flags ORDER BY 1;
SELECT unnest(heap_tuple_infomask_flags(x'FFFF'::int, x'FFFF'::int, true))
AS flags ORDER BY 1;
SELECT unnest(heap_tuple_infomask_flags(-1, -1, false))
AS flags ORDER BY 1;
SELECT unnest(heap_tuple_infomask_flags(-1, -1, true))
AS flags ORDER BY 1;
-- no flags
SELECT unnest(heap_tuple_infomask_flags(0, 0, false));
SELECT unnest(heap_tuple_infomask_flags(0, 0, true));
DROP TABLE test1;
-- check that using any of these functions with a partitioned table or index
-- would fail
create table test_partitioned (a int) partition by range (a);
create index test_partitioned_index on test_partitioned (a);
select get_raw_page('test_partitioned', 0); -- error about partitioned table
select get_raw_page('test_partitioned_index', 0); -- error about partitioned index
-- a regular table which is a member of a partition set should work though
create table test_part1 partition of test_partitioned for values from ( 1 ) to (100);
select get_raw_page('test_part1', 0); -- get farther and error about empty table
drop table test_partitioned;
-- check null bitmap alignment for table whose number of attributes is multiple of 8
create table test8 (f1 int, f2 int, f3 int, f4 int, f5 int, f6 int, f7 int, f8 int);
insert into test8(f1, f8) values (x'7f00007f'::int, 0);
select t_bits, t_data from heap_page_items(get_raw_page('test8', 0));
select tuple_data_split('test8'::regclass, t_data, t_infomask, t_infomask2, t_bits)
from heap_page_items(get_raw_page('test8', 0));
drop table test8;